Three-dimensional printing is a type of computer-based printing that creates a three-dimensional object by progressively depositing material onto a substrate (i.e., a printable surface). The concept of three-dimensional printing has been around for over thirty years, but availability of the technology has been limited commercially until the last several years. In many current three-dimensional printing systems, an ink-jet-type printer is used to serially print a material such as a thermoplastic, a metal alloy, or a plaster as layers of particles or three-dimensional dots on the substrate. Computer-control of the location and number of such layers can direct so-called “additive manufacturing” of a designed article.
Additive manufacturing (AM) process defines a process wherein digital 3-D design data is utilized to deposit materials one layer at a time to build up a component. The term “3-D printing” is frequently used as a synonym for AM. 3-D printing techniques are considered AM processes because they involve the application of successive layers of materials. Current commercial 3-D printers can selectively extrude thermoplastic, cure photosensitive resins, and sinter metallic, ceramic or polymer powders into designs that can be drawn with a computer-aided design program. The material selection combined with hardware (printer) and software is key for rapid prototyping and cost-effective manufacturing. Thermoset materials used in 3-D printing often require curing and post curing. Extrusion printer technology forces thermoplastics through a heated zone to build 3-D structures. 3-D printing structures are frequently formed using Stereolithographic technology (also known as optical fabrication, photo-solidification, solid free-form fabrication, solid imaging and Resin printing), producing models, prototypes, patterns, and production parts. Stereolithography is an additive manufacturing process that uses photosensitive thermoset resins or photo-reactive resins that are cured with a UV laser or similar power source. However, this process has been found to be too slow and expensive for 3-D printing and is not compatible with compositions that contain light-scattering particles fillers, pigment, waxes etc.
Currently, various materials are being used in three-dimensional (3D) printers. Various materials may include, for example, plastic (for example, an acrylonitrile-butadiene-styrene (ABS) resin or acrylic materials), metal (for examples, stainless steel or silver), rubber, ceramic materials, or biomaterials, or food (for examples, chocolate or powder). Also, even the same material may have different properties, for example, a thermal resistance that is a degree to which materials resist heat, a durability that is a degree to which materials endure, or a low-temperature resistance that is a degree to which materials resist a low temperature.